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101.
GPS地壳形变监测网应变解算方法与程序设计 总被引:5,自引:2,他引:5
分析了在平面直角坐标系和大地坐标系内解算应变的方法及其特点,并以Matlab为开发平台,研制出一套在平面直角坐标系和大地坐标系中解算应变的程序GPSstrain。利用GPS监测网测站位移(速率),该程序能够解算剪切应变(γ1、γ2)、面应变、块体旋转、主应变及其方向、最大剪切应变及其方向,同时也可解算出这些应变分量的误差。另外该程序还具有高斯投影解算功能,根据各测站坐标能够自动形成所有的Delaunay三角形,并以图形方式显示。最后以实际算例给出了该解算程序的部分结果,并进行了初步的分析和讨论。 相似文献
102.
地质灾害成因复杂,其中以气象因素、地质地貌因素引发的地质灾害最为常见.以金华地区为例,通过对金华市地质地貌条件及其对地质灾害点的调查,将全区划分为4个地质灾害隐患风险等级的网格区域.在此基础上利用金华中尺度气象资料,采用BP神经网络模型,建立地质灾害细网格预报模型,对该模型进行模拟和预报试验.结果表明,合理的隐患风险等级分区能使预报模型更符合科学规律,而采用分布较细的中尺度资料作为预报因子能进一步提高预报精度.模型的预报结果达到一定的可信度,为防灾减灾工作提供了科学依据. 相似文献
103.
Pin-Song Zhao Hong Wu Cong Kevin Xu Ming Yang Fan Yang Yi-Nan Zhu Man I Lam Jun-Jie Jin Hai-Long Yuan Hao-Tong Zhang Shi-Yin Shen Jian-Rong Shi A-Li Luo Xue-Bing Wu Yong-Heng Zhao Yi-Peng Jing 《天文和天体物理学研究(英文版)》2019,(8)
We present optical luminosity functions(LFs) of galaxies in the~(0.1) g,~(0.1) r,~(0.1) i bands, calculated using data in~40 deg~2 sky area of the LAMOST Complete Spectroscopic Survey of Pointing Area(LaCoSSPAr) in the Southern Galactic Cap. Redshifts for galaxies brighter than r = 18.1 were obtained mainly with LAMOST. In each band, LFs derived using both parametric and non-parametric maximum likelihood methods agree well with each other. In the0.1 r band, our fitting parameters of the Schechter function are φ_*=(1.65 ± 0.36) × 10~(-2) h~3 Mpc~(-3), M_*=-20.69 ± 0.06 mag and α =-1.12 ± 0.08,which agree with previous studies. Separate LFs are also derived for emission line galaxies and absorption line galaxies. The LFs of absorption line galaxies show a dip at~(0.1) r ~18.5 and can be fitted well by a double-Gaussian function, suggesting a bimodality in passive galaxies. 相似文献
104.
105.
海洋导管架平台的极限强度分析 总被引:5,自引:1,他引:5
海洋导管架平台的极限分析是一项较新的研究课题,随着海上采油事业的飞速发展,它已越来越受到海洋工程设计及维修部门的重视。其研究成果不仅能用于设计结构的应力校核,尚可用于现有平台结构的整体安全估算。本文利用非线性模拟技术及线性分析程序的完美结合。成功地分析计算了受集中哉茶作用的空间框架结构,及受静载荷和环境载荷作用下的真实导管架平台极限强度。 相似文献
106.
Shanwu Zhang Yun Qiu Hangyu Chen Junqiang Shen Junpeng Zhang Jing Cha Fuwen Qiu Chunsheng Jing 《海洋学报(英文版)》2021,40(11):1-10
Near-inertial motions contribute most of the velocity shear in the upper ocean. In the Bay of Bengal (BoB), the annual-mean energy flux from the wind to near-in... 相似文献
107.
���������ֽ�ؿ��α������о� 总被引:1,自引:1,他引:0
?????????????????????У???????????????????????????????о????????????α????????????????????????????????λ???????????С?????????????????????????????????????????У??????????λ??????????????????????????????????????????????????????????????????????????????????????????????????????????????Ч??????????????????????????????????????????????????????е????????С??????????????????????????α????????????????????????????????????????????Ш???????????? 相似文献
108.
The diel vertical migration(DVM) of zooplankton and the influence of upwelling on zooplankton biomass were examined using water column data of current velocity and mean volume backscattering strength(MVBS)collected by moored acoustic Doppler current profilers(ADCPs) deployed in the southeastern Chukchi Sea during the 5th Chinese National Arctic Research Expedition(CHINARE) in summer 2012, combined with the satellite observational data such as sea surface temperature(SST), wind, and chlorophyll a(Chl a). Hourly acoustic data were continuously collected for 49-d in the mooring site. Spectral analysis indicated that there were different migrating patterns of zooplankton, even though precisely classifying the zooplankton taxa was not available. The prevailing 24-h cycle corresponded to the normal DVM with zooplankton swimming upwards at sunrise and returning to deep waters at sunset. There was a clear DVM in the upper 17 m of the water column during the period with distinct day-night cycles, and no active DVM throughout the water column when the sun above the horizon(polar day), suggesting that light intensity was the trigger for DVM. Also there was a second migrating pattern with 12-h cycle. The upwelling event occurring in the northwest of Alaskan coastal area had important influence on zooplankton biomass at the mooring site. During the upwelling, the SST close to the mooring site dropped significantly from maximal 6.35°C to minimal 1.31°C within five days. Simultaneously, there was a rapid increase in the MVBS and Chl a level, suggesting the aggregation of zooplankton related to upwelling. 相似文献
109.
110.
Shijie LI Shijie WANG Huiming BAO Bingkui MIAO Shen LIU Ian M. COULSON Xiongyao LI Yang LI 《Meteoritics & planetary science》2011,46(9):1329-1344
Abstract– The Grove Mountains (GRV) 021663 meteorite was collected from the Grove Mountains region of Antarctica. The meteorite is composed primarily of olivine (Fa5.4), orthopyroxene (Fs4.7Wo3.0), chromian diopside (En53.6Fs2.4Wo44), troilite, kamacite, and plagioclase (Ab74.5Or4An21.5). Minor phases include schreibersite and K‐feldspar. The meteorite is highly weathered (W3) and weakly shocked (S2). We determine a whole rock oxygen isotopic composition of δ18O = 7.50‰, δ17O = 3.52‰. Comparisons of these data with other primitive achondrites have resulted in the reclassification of this meteorite as a member of the winonaite group. The occurrences of troilite, metal, and schreibersite in GRV 021663 indicate that these minerals were once completely molten. Euhedral inclusions of pyroxene within plagioclase further suggest that these may have crystallized from a silicate melt, while the depletion of plagioclase, metal, and troilite indicates that GRV 021663 could represent a residuum following partial melting on its parent asteroid. Trace element distributions in silicate minerals do not, however, confirm this scenario. As with other winonaite meteorites, the formation of GRV 021663 probably relates to brecciation and mixing of heterogeneous lithologies, followed by varying degrees of thermal metamorphism on the parent body asteroid. Peak metamorphic conditions may have resulted in localized partial melting of metal and silicate mineralogies, but our data are not conclusive. 相似文献